Investigation on the production of bioethanol from black tea waste biomass in the seawater-based system

The present study is aimed to utilize the seawater-based system for the production of bioethanol from black tea waste generated after the first brewing to reduce the consumption of freshwater in bioethanol industries. Two yeast isolates (Zygosaccharomyces bailii MTCC 8177 and Brettanomyces claussenii MTCC 7801) from kombucha black tea were evaluated for the ethanol production due to their growing capability in black tea brew as well as in seawater. The results revealed that the boiling process releases higher fermentable sugars from black tea waste than the other pretreatment methods studied. Among the two yeasts (Zygosaccharomyces bailii and Brettanomyces claussenii) studied for bioethanol production in the seawater-based medium, immobilized cells of Z. bailii had six-fold greater yield than the free cells. In the case of B. claussenii cells, there was no significant difference in ethanol yield between the free and immobilized cells on glucose fermentation.